I made some L-Rod clamps from a block oak wood, I have also made them out off plastic 2×4 lumber and the plastic works even better.
2-7/8″ x 1-3/8″ x 4″ block of oak wood painted black.
Drilled a 1-1/4″ hole through the block and a 7/8″ hole 1-3/4″ deep for the L-rod.
Drilled 11/32″ for the threaded insert and 19/64″ hole for the t-nut.(Check the package for correct hole size for threaded inserts and t-nuts they may be different for different brands.)
Arrow show where I cut a slot with double bladed hacksaw. Used vice to press the knobs on the 1/4″ socket cap screws.Socket Head Cap Screw Part # 91251A542 and Knobs Part # 94052A141 http://www.mcmaster.com
The L-Rods can be expensive and hard to find. You can also make your own L Rods using .79 cent anchor bolts .
I have also made the clamps using plastic 2 x 4 lumber. They are easy to make. The images are self explanatory. Knobs can also be pressed on to the socket cap screws. I found out these work the best using plastic.
You can use them with the 7/8 L-Rods or the cymbal arms.
Make your own L-Rods. Make the hole a little smaller then the thread size for the home made L-Rod. These bolts are about 10″ long and will fit a 1/2″ hole. I was able to bend them using a bench vice and a 3′ pipe.